Honeycomb core forming restricter

ABSTRACT

A portable version of a honeycomb core forming restricter (20) for forming and shaping a workpiece made of stiff honeycomb core material, the apparatus (20) to be used in combination with a press including a male die (70) and a female die (72), the apparatus (20) including: (a) a base plate (62); (b) four support tower assemblies (24a, 24b, 24c, 24d) supported by the base plate (62); (c) two shafts (22a, 22b) supported by the support tower assemblies (24a, 24b, 24c, 24d), the shafts (2a, 22b) being arranged in a generally parallel relationship to each other and to the longitudinal axis of the female die 72; (d) a carrier sheet (74) for supporting the workpiece, the carrier sheet (74) being attached to the two shafts (22a, 22b); (e) four air motors (26a, 26b, 26c, 26d) for applying rotational torque to the shafts ( 22a, 22b); and (f) the support tower assemblies including a double acting air cylinder (36a) for moving the shaft (22a) in a transverse direction with respect to the longitudinal axis of the female die (72) and a pivoting mount (48a) for allowing the centerpoint of the shaft (22a) to move in an arc in a plane transverse to the longitudinal axis of the female die (72). A dedicated version of the honeycomb core forming restricter is also disclosed.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to an apparatus and process for forming tightradii in stiff honeycomb core material using a molding press andhoneycomb forming dies. The invention enables the formation of radiithat are tighter than those which can be formed using currentlyavailable methods.

2. Description of the Background Art

Prior to this invention, for applications where a tight radius orcurvature in the finished honeycomb core material was required, either aflexible honeycomb core material or a build-up of honeycomb wedgesbonded together was used instead of one piece of stiff honeycomb corematerial because of the inability to form stiff honeycomb core materialin a tight radius without causing damage to the honeycomb core material,specifically, the damage would be core splits or cell separation at thecell nodes.

SUMMARY OF THE INVENTION

The present invention, which we call the honeycomb core forming arestricter, solves the foregoing problem and provides a means of formingstiff honeycomb core material in a variety of tight radii withoutcausing cell separation at the cell nodes.

In one aspect, the present invention is an apparatus for forming andshaping a preheated workpiece made of honeycomb core material, theapparatus to be used in combination with a press including a male dieand a female die, the apparatus including: (a) a carrier sheet forsupporting the workpiece; (b) two shafts supporting the carrier sheet,the shafts being arranged in a generally parallel relationship to eachother and to the longitudinal axis of the female die; (c) one or moremotors for applying rotational torque to the shafts; and (d) supportstructures including structures for supporting the shafts and structuresfor allowing the shafts to move with the workpiece during the formingprocess without losing contact with the workpiece.

In another aspect, the invention is a basic process of forming andshaping a preheated workpiece made of honeycomb core material using apress including a male die and a female die, where the process includesthe steps of: (a) providing a carrier sheet for supporting theworkpiece, the carrier sheet being suspended in midair by two shaftssupported by support tower assemblies; (b) loading the preheatedworkpiece onto the carrier sheet suspended in midair; (c) applyingrotational torque to the shafts whereby the carrier sheet is wrappedaround the shafts thereby applying tension to the carrier sheet andpulling the shafts toward each other and into pressing contact with thesides of the workpiece while the carrier sheet supports the bottomsurface of the workpiece; (d) closing the male and female dies againstthe workpiece while maintaining the shafts in pressing contact with thesides of the workpiece and while the carrier sheet supports the bottomsurface of the workpiece, whereby the workpiece is formed and shapedinto a formed workpiece of desired contour; and (e) opening the male andfemale dies and removing the formed workpiece.

In yet another aspect, the present invention is a preferred process offorming and shaping a preheated workpiece made of honeycomb corematerial into a complex contour using a press including a male die and afemale die having a contoured vertical retaining wall on one side of thedie, where the process includes the steps of: (a) providing a carriersheet for supporting the workpiece, the carrier sheet being suspended inmidair by two shafts supported by support tower assemblies; (b) loadingthe preheated workpiece onto the carrier sheet suspended in midair; (c)applying rotational torque to the shafts whereby the carrier sheet iswrapped around the shafts thereby applying tension to the carrier sheetand pulling the shafts toward each other and into pressing contact withthe sides of the workpiece while the carrier sheet supports the bottomsurface of the workpiece; (d) forcing the workpiece against the verticalretaining wall thereby causing the workpiece to take on the contour ofthe retaining wall; (e) closing the male and female dies against theworkpiece while maintaining the shafts in pressing contact with thesides of the workpiece and while the carrier sheet supports the bottomsurface of the workpiece, whereby the workpiece is formed and shapedinto a formed workpiece of desired complex contour; and (f) opening themale and female dies and removing the formed workpiece.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the invention, and to show how the samemay be carried into effect, reference will now be made, by way ofexample, to the accompanying drawings. In the different figures,elements designated by like reference numerals have correspondingfunctions.

FIG. 1 is a simplified perspective view showing a portable honeycombcore forming restricter in combination with a press including a male die(shown partially cutaway) and a female die.

FIGS. 2-5 show a currently available method that does not employ thepresent invention and that produces a defective product having coresplits (shown in FIG. 5).

FIG. 2 is a simplified vertical sectional view showing a press includinga male die and a raw workpiece of stiff honeycomb core material placedin a female die. As stated above, FIG. 2 does not show the presentinvention.

FIG. 3 is a simplified vertical sectional view of the apparatus of FIG.2 where the male die has partially descended against the workpiece ofstiff honeycomb core material. As stated above, FIG. 3 does not show thepresent invention.

FIG. 4 is a simplified vertical sectional view of the apparatus of FIG.2 where the male die has fully descended against the workpiece of stiffhoneycomb core material. As stated above, FIG. 4 does not show thepresent invention.

FIG. 5 is a perspective view of the defective product of stiff honeycombcore material produced in FIG. 4. FIG. 5 shows the core splits caused bycell separation at the cell nodes of the stiff honeycomb core material.As stated above, FIG. 5 is not the product of the present invention.

FIGS. 6-10 are simplified drawings that show a process for using thepresent invention to form a stiff honeycomb core workpiece into a simplecontour (the product shown in FIG. 10).

FIG. 6 is a simplified vertical sectional view of a press including amale die, a raw workpiece of stiff honeycomb core material locatedbetween the male die and the honeycomb core forming restricter of thepresent invention, and a female die.

FIG. 6A is a simplified vertical sectional view of the apparatus of FIG.6 showing the male die, the raw workpiece of stiff honeycomb corematerial supported on the honeycomb core forming restricter of thepresent invention, and the female die. In FIG. 6A, the longitudinalshafts of the honeycomb core forming restricter are pressing against thelongitudinal sides of the workpiece.

FIG. 7 is a simplified vertical sectional view of the apparatus of FIG.6A where the male die has partially descended and is touching theworkpiece of stiff honeycomb core material supported on the honeycombcore forming restricter of the present invention, and the female die. InFIG. 7, the honeycomb core forming restricter also continues to pressagainst the sides of the workpiece.

FIG. 8 is a simplified vertical sectional view of the apparatus of FIG.7 where the male die has descended further against the workpiece ofstiff honeycomb core material supported on the honeycomb core formingrestricter of the present invention, and the female die. In FIG. 8, themale die has forced the honeycomb core forming restricter down againstthe female die and the forming of the workpiece has started while thehoneycomb core forming restricter continues to press against the sidesof the workpiece.

FIG. 9 is a simplified vertical sectional view of the apparatus of FIG.8 showing the male die now fully descended against the workpiece and thefemale die. The forming of the workpiece by the male and female dies iscomplete and the longitudinal shafts of the honeycomb core formingrestricter may now be relaxed.

FIG. 10 is a perspective view of the finished honeycomb core productproduced in FIGS. 6-9 using the honeycomb core forming restricter of thepresent invention.

FIG. 11 is an exploded view of a support tower assembly of the honeycombcore forming restricter.

In FIGS. 12-15, the male die, the carrier, and the support base are notshown in order to simplify the drawings and illustrate a preferredprocess of forming a stiff honeycomb core workpiece into a complexcontour.

FIG. 12 is a perspective view of the honeycomb core forming restricter,the honeycomb core workpiece, and the female die. FIG. 12 shows thefirst step of the process that is to locate the honeycomb core workpiecein the proper location.

FIG. 13 is a top view of the apparatus shown in FIG. 12.

FIG. 14 is a perspective view of the honeycomb core forming restricter,the honeycomb core workpiece, and the complex contour female die. FIG.14 shows the second stage of the process that is to form the ribbonsin-plane prior to forming the complex contour in the workpiece.

FIG. 15 is a plan view of the apparatus shown in FIG. 14.

FIG. 16 is a perspective view of the finished product formed in acomplex contour made by the process shown in FIGS. 12-15. In thefinished product, the ribbon follows the complex contour because ofstage two of the process that is in-plane ribbon forming.

FIG. 17 is a perspective view of the finished product produced by thebasic process of forming a workpiece into a complex contour withoutin-plane ribbon forming.

FIG. 18 is a plan view of the product shown in FIG. 17.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Before describing the preferred embodiments, it is useful to describethe basic problem that is solved by the present invention. FIGS. 2-5show the problem in that these drawings show a currently availablemethod that produces a defective honeycomb core product having coresplits. FIG. 2 shows a press including a male die 70 and a preheated rawworkpiece 76 of stiff honeycomb core (for example, carbon compositehoneycomb core) placed in a female die 72.

FIG. 3 shows the male die 70 partially descended against the workpiece76 that is now being shaped against female die 72. At this stage in FIG.3, a core split 78 is beginning to occur in workpiece 76. FIG. 4 showsmale die 70 fully descended against workpiece 76 that is now shapedagainst female die 72 and core split 78 is complete. The result isdefective product 80 having core split 78 as shown in FIG. 5. Havingthus described the basic problem represented by defective product 80,the preferred embodiments will now be described.

THE PORTABLE VERSION OF THE APPARATUS

FIG. 1 shows a portable version of the honeycomb core forming restricter20 constructed according to the principles of the invention. Apparatus20 includes a left longitudinal shaft 22a and a right longitudinal shaft22b that are arranged in a generally parallel relationship to each otherand with respect to the longitudinal axis of the female die 72 as shownin FIG. 1. Apparatus 20 is designed to be portable or removable so thatit can be removed and the press can be used for other tasks, butportability is not a requirement of the invention.

Shaft 22a is connected at one end to pneumatic or air motor 26asupported on arm 38a that is part of support tower assembly 24a. Theopposite end of shaft 22a is connected to air motor 26d supported on arm38d that is part of support tower assembly 24d. Similarly shaft 22b isconnected at one end to air motor 26b supported on arm 38b that is partof support tower assembly 24b. The opposite end of shaft 22b isconnected to air motor 26c supported on arm 38c that is part of supporttower assembly 24c. Support tower assemblies 24a, 24b, 24c, and 24d areconstructed similarly.

The longitudinal shafts 22a and 22b can be constructed of either a rigidmaterial, for making a simple contour honeycomb product, or they can beconstructed of a semi-flexible material, for making a complex contourhoneycomb product. The shafts need to be strong and rigid enough tocarry the torque applied to them by the air motors and to exert the sidepressure required of them. The semi-flexible type needs to be flexibleenough to follow the desired contour of the dies. For example, thepreferred material for the semi-flexible shafts is unreinforced ULTEM, apolyetherimide resin marketed by GE Plastics.

As shown in FIGS. 1 and 6, extending between and wrapped aroundlongitudinal shafts 22a and 22b is a carrier sheet 74 made of a hightemperature-resistant material. The carrier sheet 74 supports thepreheated workpiece 76a of stiff honeycomb core material (for example,carbon is composite honeycomb core) on its convex side as shown in FIG.8, thereby reducing the tensile strain in the honeycomb core, andthereby preventing the core split problem shown in FIG. 5. The materialused to make carrier sheet 74 has the following minimum properties.First, the material is strong enough to carry the required tension forworkpiece support. Second, the material has a minimum amount ofelasticity to give it the ability to elongate slightly as required bythe operating conditions encountered in this process. Third, thematerial needs to be compliant and flexible enough to follow the desiredcontour. Fourth, the material needs to be high temperature resistant towithstand the preheated honeycomb core (for example, the material needsto withstand temperatures up to 750° F. for a short period of time). Forexample, one type of suitable material for the carrier sheet 74 is asilicone rubber sheet made by the Mosites Corporation of Fort Worth,Tex. in a 0.1 inch thickness. Another suitable material is a wovenfiberglass material having a non-stick release coating sold under thename Bleederelease E in 5-10 mil (0.005-0.010 inch) thickness. Thepreferred material for carrier sheet 74 is a polyimide film sold underthe trademark UPILEX R, supplied by ICI Films, in a 5 mil (0.005 inch)thickness.

The honeycomb core forming restricter 20 is placed in between thehoneycomb core forming dies of a press that includes a male die 70 and afemale die 72 as shown in FIGS. 1 and 6. The honeycomb core formingrestricter 20 is located so that shafts 22a and 22b are typically, butnot necessarily, equidistant from the longitudinal axis of the femaledie 72 as shown in FIG. 6. The raw workpiece 76a of stiff honeycomb corematerial of FIG. 6 must first be preheated to a desired softeningtemperature, such as up to 750° F., as specified by the manufacturer ofthe specific honeycomb core material being employed. The heating softensthe stiff honeycomb core and makes it more flexible. The honeycomb coreworkpiece 76a, after preheating, is then placed on the carrier 74 andthe shafts 22a and 22b are rotated as shown in FIG. 6A by torque appliedto the shafts by air motors 26a, 26d, 26b, and 26c. This rotation of theshafts 22a and 22b wraps the carrier sheet 74 around the shafts andapplies tension to the carrier sheet 74. The rotation of the shafts andthe application of tension to carrier sheet 74 pulls the wrapped shafts22a and 22b toward each other and into pressing contact with thelongitudinal sides of the honeycomb core workpiece 76a as shown in FIG.6A.

The bottom surface of the honeycomb core workpiece 76a rests directly onthe top surface of the carrier sheet 74 as shown in FIG. 6A. While theshafts 22a and 22b apply a compressive preload and prevent any outwardmovement of the honeycomb core workpiece 76a, the honeycomb core formingmale die 70 and female die 72 are pressed together progressively asshown in FIGS. 7-9. The radius of the male die 70 will meet the uppersurface of the honeycomb core workpiece 76a forcing it down into theradius of the female die 72 as shown in FIG. 8, thus forming thehoneycomb core workpiece 76a in FIG. 9.

The high temperature-resistant carrier sheet 74 is flexible enough toallow the honeycomb core workpiece 76a to be pressed down, and strongenough to hold the shafts 22a and 22b at a constant distance, thuspreventing the honeycomb core cells from separating at the cell nodesand thus preventing the core split problem shown in FIG. 5.

Because of the restriction of any sideways outward movement by thehoneycomb core workpiece 76a by the wrapped shafts 22a and 22b, thecells on the upper surface the honeycomb core workpiece 76a are causedto condense in on themselves in a uniform manner. The shafts 22a and 22bmay be relaxed as soon as the dies are closed. After allowing a fewminutes for the honeycomb core workpiece 76a to cool in FIG. 9, thehoneycomb core forming male die 70 and female die 72 can be opened andthe workpiece removed. The useful finished honeycomb core formed product82 shown in FIG. 10 is the result.

As shown in FIG. 1, support tower assembly 24a includes air motor 26amounted on the interior end of arm 38a. Arm 38a slides in and out ofpivoting mount 48a in a transverse direction on slide rails 40a, 42a,and 44a mounted on the sides and bottom of arm 38a. The term "transversedirection" in this context refers to motion in a direction that istransverse with respect to the longitudinal axis of female die 72.Because arms 38a and 38d support shaft 22a, movement of arms 38a and 38din a transverse direction moves the axis of shaft 22a in a directionthat is transverse to female die 72. The slide rails 40a, 42a, and 44amove in pillow blocks that are mounted on the sides and bottom withinthe U-shaped pivoting mount 48a.

Pivoting mount 48a pivots or rotates in an arc that is in a plane thatis transverse to the longitudinal axis of female die 72, therefore arm38a also pivots or rotates in an arc that is in a plane that istransverse to the longitudinal axis of female die 72. Because arms 38aand 38d support shaft 22a, the pivoting of arms 38a and 38b in an arcthat is in a plane that is transverse to the longitudinal axis of femaledie 72 also moves the centerpoint of shaft 22a in an arc that is in aplane that is transverse to female die 72. (Further construction detailsof the support tower assembly can also be seen in FIG. 11, an explodedview of similar support tower assembly 24b that will be describedbelow.)

As shown in FIG. 1, cap plate 34a is mounted on top of pivoting mount48a. A double-acting pneumatic or air cylinder 36a is mounted underneathcap plate 34a and is connected to arm 38a. Thus, actuating the aircylinder 36a will extend or retract the arm 38a in the lateral directiondescribed above. Fixed mount 50a carries pivot pin 46a upon whichpivoting mount 48a pivots or rotates in the arc described above.

As further shown in FIG. 1, fixed mount 50a is supported on top of uppersupport column 28a. Upper support column 28a telescopes within lowersupport column 30a which thereby provides a vertical heightadjustability to tower assembly 24a. Lower support column 28a is mountedon adapter base plate 32a. Adapter base plate 32a carries pillow blockson its lower side that slide on the outer lateral rail 52 and the innerlateral rail 56 that are mounted on rail support base plate 54. Thisconstruction provides the ability to move tower assembly 24a in thelateral direction on lateral rails 52 and 56.

FIG. 1 also shows that rail support base plate 54 is slidably mounted onleft longitudinal slide rail 58 and right longitudinal slide rail 60that are mounted on top of base plate 62. This provides the ability tomove tower a assemblies 24a and 24b in the longitudinal direction onlongitudinal rails 58 and 60. Base plate 62 is reinforced by channelmembers 64, 66, and 68.

The construction details of the upper portion of support tower assembly24b are shown in exploded view FIG. 11. As shown in FIG. 11, supporttower assembly 24b includes air motor 26b that is mounted on theinterior end of arm 38b. Arm 38b slides in and out of pivoting mount 48bin a transverse direction on slide rails 40b, 42b, and 44b that aremounted on the sides and bottom of arm 38b. The slide rails 40b, 42b,and 44b move in pillow blocks 84, 94, and 104, respectively, which aremounted on the sides and bottom within the U-shaped pivoting mount 48b.

As shown in FIG. 11, cap plate 34b is mounted on top of pivoting mount48b. A double-acting air cylinder 36b is mounted underneath cap plate34b. Strap mount 86 is secured to the bottom side of cap plate 34b andstraps 88 and 90 are secured to strap mount 86. Air cylinder 36b is heldby straps 88 and 90. The rod of air cylinder 36b is connected tocoupling 92 that is connected to the vertical wall 106 of arm 38b. Thus,actuating the air cylinder 36b will extend or retract the arm 38b in thetransverse direction described above. Fixed mount 50b carries left pivotpin 100 with bushing 102 and right pivot pin 46b with bushing 96. Fixedmount 50b is mounted on column adapter plate 98 that is mounted on topof upper column 28b (which corresponds to upper column 28a in FIG. 1).Pivoting mount 48b pivots or rotates in the arc described above.

The arms 38a, 38b, 38c, and 38d support the air motors 26a, 26b, 26c,and 26d, respectively, and the shafts 22a and 22b while allowingmovement and control of the location of the shafts 22a and 22b. Themovement of the shafts 22a and 22b is required to permit uninterruptedapplication of tension to the carrier sheet 74 and side pressure on thehoneycomb core workpiece 76a while the workpiece 76a is being formed tothe desired contour. The arms move rotationally and transversely duringthe forming process shown in FIGS. 6-9 to allow the workpiece 76a tomove during the forming process. Control of the transverse motioncreates the ability to increase or decrease the amount of side pressurethat the shafts are imparting on the workpiece. This side pressure canbe adjusted from zero up to the structural limits of the workpiece.Another advantage of controlling the transverse motion is the ability tolocate the shafts to improve the workpiece handling and location. Theessential function is that the shafts move with the workpiece and do notlose contact with the workpiece during the forming process.

It should be understood that the specific construction of support towerassemblies 24a, 24b, 24c, and 24d is just one example of the variousmechanisms that can be employed to support the shafts 22a and 22b inorder to allow the shafts to move with the workpiece during the formingprocess without losing contact with the workpiece.

THE DEDICATED VERSION OF THE APPARATUS

As explained above, FIG. 1 shows a portable or removable honeycomb coreforming restricter. A dedicated or integrated version of the honeycombcore forming restricter is also within the scope of the invention. Inthe dedicated version of the invention, the honeycomb core formingrestricter is integrated into the design of the press. Specifically, thefour support tower assemblies are replaced by new support structures ofsimilar design for the same function of supporting the two longitudinalshafts. The new support structures are mounted on the walls of the pressarea or they are mounted on elements of the press itself. Thisintegrated design eliminates the need for a separate base plate for thehoneycomb core forming restricter.

Thus, the dedicated version of the honeycomb core forming restricterincludes: (a) a carrier sheet for supporting the workpiece; (b) twoshafts supporting the carrier sheet, the shafts being arranged in agenerally parallel relationship to each other and to the longitudinalaxis of the female die; (c) one or more motors for applying rotationaltorque to the shafts; and (d) support structures including structuresfor supporting the shafts and structures for allowing the shafts to movewith the workpiece during the forming process without losing contactwith the workpiece.

The basic process of utilizing the honeycomb core forming restricter toform simple or complex contours is as follows: (a) Heat the stiffhoneycomb core workpiece to the proper forming temperature for the typeof honeycomb core workpiece being used. (b) Place the workpiece on thecarrier sheet between the shafts and apply torque to the shafts to bringthem into contact with the sides of the workpiece and apply tension tothe carrier sheet. (c) The workpiece is then formed, while beingsupported by the carrier sheet and held on the sides by the shafts, andallowed to cool.

The finished product 82 shown in FIG. 10 is formed in a simple contour.A simple contour is a contour in one plane. For example, the simplecontour of product 82 in FIG. 10 is a curvature in the vertical plane.The product 82 is straight in the horizontal plane. A complex contour isa contour in more than one plane. FIGS. 12-15 show a preferred processfor using the honeycomb core forming restricter 20 to form honeycombcore material into a complex contour.

In FIGS. 12-15, the complex contour male die, the carrier sheet, and thesupport base are not shown in order to simplify the drawings and toillustrate the preferred process of forming a stiff honeycomb coreworkpiece into a complex contour.

FIG. 12 is a perspective view of the honeycomb core forming restricter20, the preheated honeycomb core workpiece 76c, and the complex contourfemale die 110. FIG. 13 is a plan view of the apparatus shown in FIG.12. FIGS. 12 and 13 show the first stage of the process which is tolocate the preheated honeycomb core workpiece 76c into the honeycombcore forming restricter 20 which is in the proper location with respectto the male die (not shown) and the female die 110. Shafts 22a and 22bpress against the longitudinal sides of workpiece 76c. In FIGS. 12-15,the lines 108 in the honeycomb core workpiece 76c are a simplified wayof indicating the ribbons and the ribbon direction in the honeycomb corematerial. The ribbon direction of a workpiece of honeycomb core materialis the direction of the continuous corrugated strips or ribbons ofmaterial which are used to construct the honeycomb material. All of thecontinuous corrugated ribbons are oriented in one direction in a rawworkpiece. The corrugated ribbons are bonded in the direction that isperpendicular to the ribbon direction in order to form the hexagonalcells that make up the honeycomb core material.

The complex contour female die 110 used in this process has a verticalretaining wall 112 on the left side of the die 110. Alternatively, theretaining wall 112 could be replaced by a multiplicity of verticalretaining pins placed in the same location as the retaining wall in FIG.12. In the first stage shown in FIG. 12, the left shaft 22a is locatedagainst the retaining wall 112 of the female die 110.

FIG. 14 is a perspective view which shows the second stage of theprocess which is to form the ribbons 108 in the horizontal plane beforeforming the complex contour in workpiece 76c. This stage is accomplishedby retracting air cylinders 36a and 36d and concurrently extending aircylinders 36b and 36c as shown by the arrows in FIG. 14.

As shown in FIG. 14, this retraction and extension of the air cylinderspulls left shaft 22a laterally to the left and forces left shaft 22aagainst the retaining wall 112, thereby bending shaft 22a againstretaining wall 112. At the same time, right shaft 22b is being pushedlaterally to the left. This forces right shaft 22b against workpiece76c. Right shaft 22b forces workpiece 76c against shaft 22a andretaining wall 112. This causes workpiece 76c to take on the contour ofretaining wall 112. Thus, this step forms the ribbons 108 of theworkpiece 76c in the horizontal plane into the contour of retaining wall112. We call this step "in-plane" forming of the ribbons. FIG. 15 showsthe in-plane forming of the ribbons 108 in a plan view.

The next stage of the process is for the complex contour male die (notshown) to descend against workpiece 76c, thereby forcing workpiece 76cdown into complex contour female die 110 while carrier sheet 74 supportsthe bottom surface of workpiece 76c. At the same time the male die isforcing workpiece 76c down, shafts 22a and 22b are continuously pressingagainst the sides of workpiece 76c while it is being formed by the diesand the carrier sheet (not shown) is supporting the bottom surface ofworkpiece 76c.

FIG. 16 is a perspective view of the finished honeycomb product 114formed in a complex contour made by the preferred process shown in FIGS.12-15. In finished product 114, the ribbons 108 follow the complexcontour because of stage two of the process which is the in-plane ribbonforming. This is the most cost-effective process for forming a honeycombworkpiece into a complex contour because there is very little or nowaste of material from trimming.

The basic process (described above in conjunction with FIGS. 6-9) ofutilizing the honeycomb core forming restricter to form a workpiece intoa simple contour product may also be used to form a complex contourproduct. The basic process produces a finished complex contour product116 as shown in perspective view in FIG. 17 and in plan view in FIG. 18.The product 116 has ribbons that follow a straight line and do notfollow the complex contour. This is because the basic process does notinclude the step of in-plane ribbon forming. Thus, the basic process ofmaking product 116 begins at stage one with a larger raw workpiece inthe apparatus shown in FIGS. 12 and 13. But stage two shown in FIGS. 14and 15 is not performed. The next stage of the basic process is for thecomplex contour male die to descend against the raw workpiece, therebyforcing the workpiece down into female die 110 while the carrier sheetsupports the bottom surface of the workpiece and shafts 22a and 22bpress against the sides of the workpiece while it is being formed by thedies.

The complex contour product of the basic process will then requiretrimming off excess honeycomb material in order to arrive at the finalproduct 116 shown in FIGS. 17 and 18. In product 116, the ribbondirection goes over the complex contour instead of following the complexcontour. The reason the basic process is not a cost effective process ofmaking the product 116 is that the process requires a larger startingworkpiece and the excess material which is trimmed off is waste.

As will be apparent to those skilled in the art to which the inventionis addressed, the present invention may be embodied in forms other thanthose specifically disclosed above, without departing from the spirit oressential characteristics of the invention. The particular embodimentsof the invention described above and the particular details of theprocesses described are therefore to be considered in all respects asillustrative and not restrictive. The scope of the present invention isas set forth in the appended claims rather than being limited to theexamples set forth in the foregoing description. Any and all equivalentsare intended to be embraced by the claims.

What is claimed is:
 1. An apparatus for forming and shaping a preheatedworkpiece made of honeycomb core material, said apparatus to be used incombination with a press including a male die and a female die, saidapparatus comprising:(a) a carrier sheet means for supporting saidworkpiece; (b) two shaft means supporting said carrier sheet means, saidshaft means being arranged in a generally parallel relationship to eachother and to the longitudinal axis of said female die; (c) means forapplying rotational torque to said shaft means; and (d) supportstructure means comprising means for supporting said shaft means andmeans for allowing said shaft means to move with said workpiece withoutlosing contact with said workpiece during the forming and shaping ofsaid preheated workpiece.
 2. The apparatus of claim 1 wherein saidsupport structure means further comprisesmeans for moving said shaftmeans in a transverse direction with respect to the longitudinal axis ofsaid female die and means for allowing the centerpoint of said shaftmeans to move in an arc in a plane transverse to the longitudinal axisof said female die.
 3. The apparatus of claim 2 wherein said means formoving said shaft means in a transverse direction with respect to thelongitudinal axis of said female die comprises a double-acting pneumaticcylinder.
 4. The apparatus of claim 2 wherein said means for allowingthe centerpoint of said shaft means to move in an arc in a planetransverse to the longitudinal axis of said female die comprises apivoting mount.
 5. The apparatus of claim 1 wherein said shaft means areflexible enough to be capable of following the contour of said male andfemale dies.
 6. The apparatus of claim 1 wherein said means for applyingrotational torque to said shaft means comprises a pneumatic motor.
 7. Anapparatus for forming and shaping a preheated workpiece made ofhoneycomb core material, said apparatus to be used in combination with apress including a male die and a female die, said apparatuscomprising:(a) a base means; (b) support tower means supported by saidbase means; (c) two shaft means supported by said support tower means,said shaft means being arranged in a generally parallel relationship toeach other and to the longitudinal axis of said female die; (d) carriersheet means for supporting said workpiece, said carrier sheet meansbeing attached to said shaft means; (e) means for applying rotationaltorque to said shaft means; and (f) said support tower means comprisingmeans for allowing said shaft means to move with said workpiece withoutlosing contact with said workpiece during the forming and shaping ofsaid workpiece.
 8. The apparatus of claim 7 wherein said support towermeans further comprisesmeans for moving said shaft means in a transversedirection with respect to the longitudinal axis of said female die andmeans for allowing the centerpoint of said shaft means to move in an arcin a plane transverse to the longitudinal axis of said female die. 9.The apparatus of claim 8 wherein said means for moving said shaft meansin a transverse direction with respect to the longitudinal axis of saidfemale die comprises a double-acting pneumatic cylinder.
 10. Theapparatus of claim 8 wherein said means for allowing the centerpoint ofsaid shaft means to move in an arc in a plane transverse to thelongitudinal axis of said female die comprises a pivoting mount.
 11. Theapparatus of claim 7 wherein said shaft means are flexible enough to becapable of following the contour of said male and female dies.
 12. Theapparatus of claim 7 wherein said means for applying rotational torqueto said shaft means comprises a pneumatic motor.